MXPA01009868A - Resilient, three dimensional polymeric film comprising capillary apertures, and absorbent article with improved backsheet comprising the film. - Google Patents

Abstract

The present invention relates to resilient, three dimensional, perforated plastic webs which allow passage of water vapour, and preferably of air, but are resistant to the transmission of aqueous fluids at least in one direction. According to the present invention the perforated plastic webs consist of a liquid impervious polymeric film comprising apertures which form capillaries having a length which is at least twice if compared to the dimension of the respective aperture in the polymeric film surface. The present invention also relates to absorbent articles like baby diapers, adult incontinence articles and in particular to sanitary napkins or pantiliners which have a topsheet on the surface facing the wearer in use. According to the present invention the articles are provided also with an apertured backsheet, preferably for breathability. The backsheet comprises at least one layer of a resilient, three dimensional, perforated plastic web as described above.

Description

FILM POLIMERIC A TRIDIMENSIONAL. RESILIENT. COMPRISING CAPILLARY OPENINGS, AND ABSORBENT ARTICLE WITH AN IMPROVED BACK SHEET THAT COMPRISES THE MOVIE FIELD OF THE INVENTION The present invention relates to perforated, resilient, three-dimensional plastic frames, which are breathable, but are resistant to the transmission of aqueous fluids in at least one direction. According to the present invention, the perforated plastic webs consist of a polymeric film impervious to liquid comprising openings which form capillaries having a length that is at least twice as compared to the size of the respective opening in the surface of the polymer film. The perforated, resilient, three-dimensional plastic frames in accordance with the present invention are preferably comprised in absorbent articles such as baby diapers, adult incontinence articles and in particular sanitary or panty-protective pads, preferably within a breathable backsheet structure. The present invention also relates to absorbent articles such as baby diapers, adult incontinence articles and in particular sanitary or panty-protective pads provided with a backsheet comprising said frames, preferably to provide breathability.

BACKGROUND OF THE INVENTION The main needs of the consumer which are situated in the development in the field of the absorbent article, in particular sanitary napkins, products t. ,. catamenial or pantiprotective is the provision of products that provide both a high level of protection and comfort. One way to provide comfort benefits for the consumer in absorbent articles is through the provision of breathable products. Respirability has typically been concentrated in the incorporation of so-called "respirable back sheets" on absorbent articles. Commonly used in breathable backsheets are microporous films and films formed with openings having directional fluid transfer as disclosed in for example U.S. Patent No. 4591523. Both of these types of breathable backsheets are permeable to steam allowing gaseous exchange with the environment. This thus allows the evaporation of a part of the fluid stored in the core and increases the circulation of air within the absorbent article. The latter is particularly beneficial as it reduces the sticky and dirty feeling experienced by users of or associated with articles comprising a film formed with openings or film-like top sheet. The use of the apertured film upper sheets has long been recognized as providing the particular benefits in controlling the liquid flow through this layer towards an absorbent structure and reducing the flow of liquid away from the absorbent structure towards the skin of the absorbent structure. an user. In this regard, the upper film sheets with openings have provided an exceptional dryness comfort to the users of the absorbent articles, particularly sanitary napkins. This comfort benefit, however, began to disappear under the stress conditions of these articles, such as the user's physical exercise (which also causes perspiration from the skin opposite the article to emanate more intensely), the heavy loads of the user. article or the duration of prolonged use.

A disadvantage associated with the use of breathable backsheets in absorbent articles is the negative effect on the functioning of the level of protection by leakage, known as rewetting, on the garments of the users. Although the respirable back sheets in principle only allow the transfer of materials in the gaseous state, physical mechanisms such as extrusion, diffusion and capillary action may still occur and result in the transfer of fluids from the absorbent core through the backsheet and onto the wearer's garments. In particular, these mechanisms come to dominate more if the product is used during physical exercise, or for considerable discharge loads, or for prolonged periods of time. Therefore, although the incorporation of breathable backsheets in absorbent articles is highly desirable from the point of view of comfort, since the main role of a backsheet still remains in the prevention of liquid leakage, the sheets Conventional breathable backs have not been successfully incorporated into the products. The problem of rewetting on users' garments due to the incorporation of said breathable backsheets into absorbent articles has also been recognized in the art. Attempts to solve the problem have resided mainly in the use of multiple layer backsheets such as those illustrated in U.S. Patent No. 4341216. Similarly, European Patent Application No. 710471 discloses a breathable back sheet comprising an outer layer of a hydrophobic, gas-permeable polymeric fibrous web, and an inner layer comprising an apertured film having directional fluid transport. The backsheet construction preferably has no liquid / rewet transport under certain specific test conditions. Also European Patent Application No. 710472 describes a breathable back sheet consisting of at least two breathable layers which are loose one from the other over the core area. The construction of the backsheet preferably does not have liquid / rewet transport under certain specific test conditions. U.S. Patent No. 4,713,068 discloses a breathable garment-type barrier to be used as an outer cover for absorbent articles. The barrier comprises at least two layers, a first layer having a specific basis weight, fiber diameter and specific pore size, and a second layer comprising a continuous film of polyvinyl alcohol having a specific thickness. The barrier also has a specific water vapor transmission rate and a level of impermeability. However, these proposed solutions have not been able to provide a completely satisfactory solution to the problem of rewetting the breathable backsheet under stress conditions. However, especially under such stress conditions, breathability would have the most pronounced comfort benefits especially for articles comprising top sheets of film.

For such articles, the tackiness, poor ventilation or residue of stains experienced or assumed between the skin and the film is much greater under conditions of stress. U.S. Patent No. 5,591, 510 as well as international publications WO 97/03818 and WO 97/03795 disclose an apertured film layer having capillaries which are arranged at an angle relative to the plane of the film, whose films are referred to as films with slanted capillaries. This film structure is provided as an improvement for the incorporation into garments and clothing that are breathable, still not transmitting the liquids towards the wearer of said garments. Also the use of said films with inclined capillaries is indicated in the context of the absorbent articles but as a . _ _ M. ^ "jj .. top sheet, particularly in Figure 16 of U.S. Patent No. 5,591, 510 the combination of said films with inclined capillaries together with an absorbent material is disclosed, however not the context of disposable absorbent articles according to the present invention. In the European patent applications Nos. 98101867.4 and 98101868.2, respectively titled "Absorbent article with breathable double layer backsheet comprising a layer with inclined capillary openings", and "Absorbent article with breathable backsheet comprising inclined capillary openings and a sheet film top with openings ", disposable absorbent articles such as baby diapers, adult incontinence articles and in particular sanitary or panty-protective pads are described. Typically, said articles comprise a liquid permeable upper sheet forming the surface that gives the body of the article, an absorbent core and a breathable back sheet forming the garment surface of the article. The absorbent core is interposed between the top sheet and the back sheet. The breathable backsheet is placed on the garment surface of the absorbent core and comprises at least one layer of the backsheet. The backsheet comprises a three-dimensional resilient web, which consists of a polymeric film impermeable to the liquid of the backsheet whose film of the backsheet has openings. The openings form capillaries which have side walls that extend away from the surface that gives the wearer the film of the backsheet and towards the absorbent core providing the weft with the three-dimensional capability. The capillaries have a first opening in the surface that gives the garment of the film of the backsheet and a second opening in the end of the capillaries separated from each other of the surface that gives the user of the backsheet film. The capillaries extend away from the surface that gives the user of the backsheet film an angle that is less than 90 ° with respect to the plane of the backsheet film, or, in X. other modalities, are curves or bend towards the plane of the film of the back sheet. In addition, alternatively or in addition to this, the capillaries may have a first and a second portion that are different in direction, shape, shape, size or combinations thereof. Also the second opening of at least some of the capillaries can be provided with slits. The slits are considered to be such shapes in which the longest extension of an opening is at least five times the length of the smallest length of the opening. Attributable to the directional transport capacity of film fluid 10 back sheet polymer and the ability to close under derivable pressure from the angled capillaries, the breathable backsheets of the aforesaid European patent applications provide an absorbent article with good continuous protection against leakage while maintaining optimum breathability for the improved comfort. 15 However, the performance of the resilient, three-dimensional polymeric films, having capillary-forming openings, and preferably inclined capillaries as described above, can still be improved in terms of resilience, and of breathability combined with the directional transport capacity of the fluid under the pressure and stress exerted on the three-dimensional resilient film during the Use, which is particularly desirable when said films are preferably comprised in breathable articles, for example in a breathable backsheet structure of the disposable breathable absorbent articles. It is therefore an object of the present invention to provide a perforated, resilient, improved three-dimensional plastic screen consisting of a film 25 polymer with openings that form capillaries. Also the operation of the disposable absorbent articles with the backsheets preferably respirable that comprise at least one three-dimensional resilient polymeric film having capillary-forming openings, and preferably inclined capillaries as described above, can still be improved in terms of breathability combined with better resistance to rewetting of the backsheet structure under the pressure and effort experienced during the use of the absorbent articles comprising said backsheets. The operation of the disposable absorbent articles can also be improved in terms of the flexibility of the backsheet structures, since the backsheets comprising a three-dimensional resilient polymeric film having openings that form capillaries can also be used in disposable absorbent articles. in a different context of breathability, for example taking advantage of the flexibility of these structures in response to the compressive forces typically exerted in use perpendicular to the surface of the film. It is therefore a further object of the present invention to provide a disposable absorbent article having a backsheet comprising an improved three-dimensional resilient polymer film with apertures forming capillaries. It is still a further object of the present invention to provide a preferably breathable disposable absorbent article having improved comfort while maintaining even better protection against leakage, i.e. it is exceptionally resistant to rewetting under the stresses and pressures experienced during use.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to perforated, resilient, three-dimensional plastic frames, consisting of a polymeric film impervious to liquid having a first surface, a second surface, and openings that form capillaries. The capillaries have side walls that extend away from the second surface of the film providing the weft with three-dimensional capability. The capillaries have a first opening having a smaller dimension Dm? N on the first surface of the film and a second opening at the end of the capillaries separated from the second surface of the film. Each of the capillaries defines a conduit constituted by the first opening, the second opening and the side walls. Each of the capillaries also has a central line defined as the axis of the conduit, and a length L measured along the center line between the first opening and the second opening. For each capillary the ratio between the length L of the conduit and the smallest dimension Dm, n of the respective first opening is greater than 2. The present invention also relates to disposable absorbent articles of a layered construction for the absorption of fluids of the body such as baby diapers, adult incontinence articles and in particular sanitary or panty-protective pads, which are preferably also breathable. Also items such as armpit sweat pads or school shirts may benefit from the present invention. Typically such articles are layered construction with each layer or group of layers having a surface that gives the garment which is oriented to face in the direction of a garment during the use of the article and a surface that gives the user facing in a opposite direction. Typically said articles comprise a liquid-permeable upper sheet that forms the surface that gives the user of the article, an absorbent core and a back sheet preferably breathable forming the surface that gives the garment of the article. The absorbent core is interposed between the back sheet and the back sheet. The preferably breathable backsheet is located on the garment surface of the absorbent core and comprises at least one backsheet layer. The backsheet comprises a three-dimensional resilient web, which consists of a polymeric film impermeable to the backsheet liquid with openings as described above, wherein the openings form capillaries having sidewalls that extend away from the surface that it gives to the user from the backsheet film to the absorbent core providing the weft with the three-dimensional capability.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a cross-sectional view of an absorbent article comprising all the common elements of said articles including a perforated, resilient, three-dimensional plastic web, according to the present invention. Figure 2 shows an enlarged cross-section of a capillary in a perforated, resilient, three-dimensional plastic frame, according to the present invention. Figures 3 to 7 show particular alternative embodiments of the inclined capillaries used for the three-dimensional screen according to the present invention. Figure 8 shows a cross-sectional view of an absorbent article similar to that of Figure 1, with a different embodiment of a perforated, resilient, three-dimensional plastic frame, comprised in an alternative structure of the backsheet.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to perforated plastic frames, resilient, three-dimensional, consisting of a polymeric film impervious to liquid having openings that form capillaries. In summary, the plots of the present invention are also identified as resilient, three-dimensional polymeric frames, having capillary openings. In a preferred embodiment of the present invention, the perforated, resilient, three-dimensional plastic frames are comprised of disposable absorbent articles for the absorption of body fluids such as sanitary napkins, panty-protectors, incontinence products and disposable diapers, more preferably in a breathable backsheet structure of said disposable absorbent articles. The present invention also relates to such disposable absorbent articles for the absorption of body fluids such as sanitary napkins, pantiliners, incontinence products, sweat pads and baby diapers. Typically these articles comprise the elements of a liquid pervious top sheet, a back sheet and an intermediate absorbent core to the top sheet and the back sheet. According to the present invention the top sheet, the back sheet, and the core can be selected from any of the known types of these components as long as they meet the desired comfort and protection performance requirements and the conditions noted below and in the attached claims. The perforated, resilient, three-dimensional plastic frames according to the present invention can however be included in any other type of article, or else be used as such, as a frame that provides . ^ -. j »., - ai« respirability, ie water vapor permeability and preferably air permeability, and directional transport capacity of the liquid, for example, in agriculture. For example, the perforated, resilient, three-dimensional plastic frames according to the present invention can take advantage of an increased resistance against rewetting, provided by a better directional transfer capability of the fluid under stress conditions, for example under pressure and combined with the permeability to water vapor and preferably to air, when they are comprised in for example other articles than disposable absorbent articles, such as for example gowns, facial masks, bandages, where breathability and resistance to fluid transmission in less an address under particularly stressed conditions are highly desirable. Also items such as armpit sweat pads or school shirts may benefit from the present invention. Resilient, three-dimensional polymeric webs according to the present invention may also be used in a context other than breathability, for example by taking advantage of an improved flexibility of these structures in response to the compressive forces typically exerted perpendicularly in use of the surface of the film. These can be used for example in a backsheet of a disposable absorbent article which is not breathable in order to provide the resilience and cushioning effect. The perforated plastic frames resilient, three-dimensional, of the present invention will be described hereinafter with reference to preferred embodiments where these are comprised in a preferably breathable backsheet structure of a disposable absorbent article such as a sanitary napkin, but the wefts of the present invention may also be comprised in other elements than a backsheet structure, for example, as a top sheet, in disposable absorbent articles, or also in other types of articles as explained above. Therefore, in the following description, the references to the three-dimensional, resilient, perforated plastic frames of the present invention as a backsheet polymer film only represents an example of a preferred embodiment of the present invention. Typically said preferred disposable absorbent articles comprise the elements of a liquid permeable top sheet, a back sheet and an absorbent core intermediate the top sheet and the back sheet. According to a preferred embodiment of the present invention the top sheet, the back sheet and the core can be selected from any of the known types of these components as long as they meet the desired comfort and protection performance requirements and the conditions outlined below. and in the appended claims. In general, the upper sheet if present must have said liquid retention to maintain a dry surface and thus keep the user's skin dry; the absorbent core needs to provide sufficient absorbent capacity and allow steam and / or air to flow through it and the backsheet must prevent rewetting (liquid permeability) to retain the absorbed fluid while also being preferably breathable. In addition, the individual elements are joined, preferably using techniques such that the final product has the desired level of performance and comfort. In the following description of the invention the surface that is in the direction of the user is called the surface that it gives to the user. In the drawings, this direction is indicated by the arrow 20. In addition, the surface that it gives in the direction of the garment is called the surface that gives the garment and in the drawings this direction is indicated by the arrow 21.

^ -.- L-te.- The disposable absorbent article is described below with reference to a preferred embodiment of the present invention, wherein the article is also breathable and has a breathable backsheet comprising the three-dimensional resilient weft having capillary openings of the present invention. However, the three-dimensional resilient polymeric web having capillary openings comprised in the backsheet can also be used in the context of a non-respirable absorbent article, for example for the purpose of providing an improved flexibility and cushioning effect in response to the forces of compression typically exerted during use perpendicular to the surface of the weft.

Components of the absorbent article The upper sheet According to a preferred embodiment of the present invention the absorbent article usually comprises a topsheet. In a disposable absorbent article the topsheet generically comprises the uppermost layer or layers intended to be directly in contact with the wearer's body. The upper sheets suitable for use herein can be any type of topsheet known in the art. In Figure 1 the top sheet is indicated by the reference number 30. The top sheets for use herein may comprise a single layer or a multiplicity of layers. In a preferred embodiment the top sheet comprises a first layer which provides the surface that gives the user of the top sheet and a second layer between the first layer and the absorbent structure / core.

In addition the other layer on the surface that gives the user of the first layer however only extends the central zone or in parts of the peripheral area of the article may be desirable to provide additional softness or additional liquid handling / retention capabilities (this design it is usually referred to as "hybrid top sheet"). The topsheet typically extends through the entire absorbent structure and can extend into and form part of all or the side flaps, side wrapping elements or preferred wings. Also, the top sheet (or instead of at least one layer thereof) can wrap around the absorbent core, thus providing a top sheet layer and a layer that is considered part of the back sheet. The upper sheet as a whole and therefore each layer individually needs to be docile, soft feeling, and non-irritating to the wearer's skin. This can also have elastic characteristics that allow it to be stretched in one or two directions. As used herein, the top sheet therefore refers to any layer or layer combinations whose primary function is the acquisition and transport of the fluid from the user to the absorbent core and the containment of the absorbent core.

In addition, the topsheet of the present invention should have a high vapor permeability, preferably also a high air permeability. According to the preferred embodiment of the present invention the topsheet can be formed from any of the materials available for this purpose and known in the art, such as woven materials, non-woven materials, films or combinations thereof. In a preferred embodiment of the present invention at least one of the layers of the topsheet comprises a polymeric film with openings, permeable to liquid. A layer, but preferably the layer facing towards and in contact with the user, is provided by a film material having openings which are provided to facilitate the transport of liquid from the surface which gives the user towards the absorbent structure. Said films with openings, permeable to liquid, are well known in the art. These provide a three-dimensional resilient fiber structure. Such films have been disclosed in detail for example in U.S. Patent No. 3,929,135, U.S. Patent No. 4,151, 240, U.S. Patent No. 4,319,868, U.S. Patent No. 4,324,246, U.S. Pat. from United States No. 4,342,314, United States Patent No. 4,591, 523, United States Patent No. 4,609,518, United States Patent No. 4,629,643, United States Patent No. 4,695,422 or International Publication WO 96/00548 . An example of such a film is available from Procter & Gamble Company, Cincinnati, Ohio, USA under the trade name Dryweave. Also said films are available from the Pantex company in Pistoia, Italy under the designation "PF films". Also the film according to U.S. Patent No. 5,591, 510 or international publications Nos. WO 97/03818 and WO 97/03795 described for use as a layer in breathable backsheets, may be employed or may require the modification of the openings to ensure the permeability of the liquid from the surface that gives the user to the absorbent core which is the primary objective of the upper sheet and the layers that constitute it. Said modification may for example be an alteration of surface energy which actively conducts the liquids inwards and through the openings creating a gradient of surface tension of the film. A method for providing surface energy gradients is described for example in the international publication WO / 96 00548. A particularly preferred design would then be to use the same film for the top sheet and the backsheet both possibly reinforced by additional layers. Said film is for example wrapped around and surrounds the absorbent core and is treated for the transport of liquid towards the absorbent core in the area corresponding to the upper sheet but is not treated in the area corresponding to the longitudinal sides and the sheet posterior (or treated to prevent migration of liquid from the absorbent core through the posterior sheet). The treatment in the area corresponding to the top sheet can for example provide a discontinuous coating of hydrophobic silicone on the surface which gives the user in line with the international publication WO 96/00548. In addition to or alternatively, the characteristics of the openings can be made differently (ie, for liquid transport) in the area of the film corresponding to the upper sheet.

Absorbent core According to a preferred embodiment of the present invention absorbent cores suitable for use herein can be selected from any of the absorbent cores or core systems known in the art. As used herein the term "absorbent core" refers to any material or multiple layers of material whose primary function is to absorb, store and distribute the fluid.

In Figure 1, the absorbent structure is shown to comprise 3 layers, 40, 42 and 44. The absorbent core of the present invention should have a high vapor permeability, preferably also a high air permeability. The absorbent core preferably has a gauge or thickness less than 12 mm, preferably less than 8 mm, more preferably less than 5 mm, most preferably from 4 mm to 2 mm. According to the preferred embodiment of the present invention, the absorbent core can include the following components: (a) a primary optional fluid distribution layer preferably together with a secondary optional fluid distribution layer; (b) a fluid storage layer; (c) a layer J ^. optional fibrous ("dedusting") that is located below the storage layer; and (d) other optional components.

Primary / secondary layer of fluid distribution An optional component of the absorbent core according to the present invention, indicated as the layer 40 in Figure 1, is a primary fluid distribution layer and the secondary fluid distribution layer. The primary distribution layer is typically below the top sheet and is in fluid communication with it. The top sheet transfers the acquired fluid to this primary distribution layer for final distribution to the storage layer. This transfer of fluid through the primary distribution layer not only occurs within the thickness, but also along the length and width directions of the absorbent product. The also optional but preferred secondary distribution layer is typically below the primary distribution layer and is in fluid communication with it. The purpose of this secondary distribution layer is to easily acquire the fluid from the primary distribution layer and transfer it rapidly to the underlying storage layer. This helps the fluid capacity of the underlying storage layer to be fully utilized. The fluid distribution layers can be comprised of any typical material for said distribution layers.

Fluid storage layer Positioned in fluid communication with, and typically being below, the primary or secondary distribution layers, is a fluid storage layer 42. The fluid storage layer can comprise any material ri ', rA ^ *' '- * - J i common absorbent or combinations thereof. This preferably comprises gelling absorbent materials usually referred to as "hydrogel", "superabsorbent", "hydrocolloid" materials in combination with suitable carriers, which are indicated as the particles 43 in Figure 1. The gelling absorbent materials are capable of absorbing large quantities of aqueous fluids from the body, and they are also capable of retaining said absorbed fluids under moderate pressures. The gelling absorbent materials may be dispersed homogeneously or non-homogeneously in a suitable carrier. Suitable carriers, provided they are absorbent as such, can also be used alone. The gelling absorbent materials suitable for use herein will very often comprise particles of a substantially water-insoluble, slightly crosslinked, partially neutralized polymeric gelling material. This material forms a hydrogel when in contact with water. Such polymeric materials can be prepared from polymerizable, unsaturated, acid-containing monomers, which are well known in the art. Suitable carriers include materials that are conventionally used in absorbent structures such as natural, modified or synthetic fibers, particularly modified or unmodified cellulose fibers, in the form of fluff and / or tissue. Suitable carriers can be used together with the gelling absorbent material, however, these can also be used alone or in combinations. Tissue and tissue laminates are very preferred in the context of sanitary napkins and pantiliners. One embodiment of the absorbent structure made in accordance with the present invention comprises a two-ply tissue laminate. These layers can be joined to each other for example by adhesive or by melting a polymeric binder in - *? dust (for example, polyethylene powder), mechanical interlacing, or hydrogen bridge bands. The gelling absorbent material or other optional material may be comprised between the layers. Modified cellulose fibers such as hardened cellulose fibers can also be used. Synthetic fibers can also be used and include those made of cellulose acetate, polyvinyl fluoride, polyvinylidene chloride, acrylics (such as orlon), polyvinyl acetate, non-soluble polyvinyl alcohol, polyethylene, polypropylene, polyamides (such as nylon) , polyesters, two-component fibers, three-component fibers, mixtures thereof and the like. Preferably, the surfaces of the fiber are hydrophilic or are treated to be hydrophilic. The storage layer may also include filling materials, such as perlite, diatomaceous earth, vermiculite, etc., to improve liquid retention. If the gelling absorbent material is dispersed in an inhomogeneous manner in a carrier, the storage layer may, however, be locally homogeneous, ie have a distribution gradient in one or several directions within the dimensions of the storage layer. . The inhomogeneous distribution can also refer to laminates of carriers that enclose partially or totally gelling absorbent materials. An alternative is foam-type or real-foam structures such as liquid storage. There are open cell foams that absorb liquid and the continuous or superficial chemical interaction retains the liquid also under pressure. Typical foams in this context are for example those disclosed in PCT publications WO 93/03699, WO 93/04092, WO 93/041 13. 5 Optional fibrous layer ("dedusting") zr? l? r ^ tj ^ é ^ kéá ^.

An optional component for inclusion in the absorbent core according to the present invention is a fibrous layer adjacent to, and typically being below, the storage layer identified by reference numeral 44 in Figure 1. This underlying fibrous layer is typically referred to as a 5"dedusting" layer as it provides a substrate on which the gelling absorbent material is deposited in the storage layer during the manufacture of the absorbent core. In fact, in those instances where the gelling absorbent material is in the form of macro structures such as fibers, sheets or strips, this fibrous "dedusting" layer need not be included. However, this 0"dedusting" layer provides some of the additional fluid handling capabilities such as rapid capillary action of the fluid along the length of the pad.

Other optional components of the absorbent structure The absorbent core according to the preferred embodiment of the present invention may include other optional components normally present in the absorbent webs. For example, a reinforcing fabric may be placed within the respective layers, or between the respective layers, of the absorbent core. Said reinforcement canvases must be of such configuration so as not to form interfacial barriers for fluid transfer. Given the structural integrity that commonly occurs as a result of thermal bonding, reinforcing canvases are not usually required for thermally bonded absorbent structures. Another component that can be included within the absorbent core according to the invention, and preferably is provided near or as part of the primary or secondary fluid distribution layer or the fluid storage layer, are the odor control agents such as zeolites, carbon black, silicates, EDTA or other chelates. These agents are preferably provided in the form of particles or as part of the particles and may be provided together with the aforementioned gelling absorbent material.

Back sheet The absorbent article according to the preferred embodiment of the present invention also comprises a breathable backsheet. The back sheet mainly has to prevent the exudates absorbed and contained in the absorbent structure from wetting the articles that are in contact with the absorbent product such as underpants, briefs, pajamas, undergarments, shirts or jackets, thus acting as a barrier for the fluid transport. In addition, however, a preferred breathable backsheet of the present invention allows the transfer of at least water vapor, preferably both water vapor and air through it and thus allows the circulation of air in and out of the air. the water vapor out of the article. The backsheet typically extends through the entire absorbent structure and can extend into and form part or all of the side flaps, side wrapping elements or wings, if present. In accordance with the preferred embodiment of the present invention, the suitable breathable backsheet for use herein comprises at least one layer of polymeric backsheet impervious to liquid. The backsheet comprises a three-dimensional resilient web according to the present invention, which consists of a liquid impervious film having capillary openings and is permeable to air. Preferred breathable backsheets for use herein are those that have a high vapor exchange, most preferably both high vapor exchange and high air exchange. The film with capillary openings .L .. it is oriented in such a way that it retards or prevents the passage of liquid from the absorbent core to the outside while allowing the free flow of air through it. In accordance with the preferred embodiment of the present invention, any additional layer of the backsheet needs to provide at least the water vapor permeability to support the breathability of the article. It is not required but it is desirable that it also supports air permeability in order to further improve the comfort benefit from the breathability of the article. In this context suitable water vapor and air permeable layers include micro or macro perforated two dimensional films, which may also be micro or macroscopically expanded films, films formed with apertures and monolithic films, as well as woven or nonwoven materials. Said films are disclosed in detail for example in the European document EP 293482 and in references thereto, or United States patent No. 3,929,135, United States patent No. 4,637,819 and in United States patent No. 4,591,523. The three-dimensional, resilient polymeric web, according to the preferred embodiment of the present invention, provides permeability to air and water vapor by being perforated. In a preferred embodiment of the present invention illustrated in Figure 1, the breathable disposable absorbent article, which may be for example a sanitary napkin or a pantyhose, comprises a breathable backsheet 50. The breathable backsheet 50 comprises a polymeric film, three-dimensional resilient impermeable to the backsheet liquid 55 constituted by the three-dimensional resilient polymeric web of the present invention and having a first surface corresponding in this embodiment to a surface giving the garment and a second surface corresponding to a surface that gives the user, both surfaces being flat and parallel to each other, and also parallel to the plane P of the backsheet film55. In the embodiment of the present invention shown in Figure 1, the plane P actually corresponds to the garment facing surface of the backsheet film 55. The terms "planar" and "planar" as used herein refer to the configuration of the backsheet film 55 as such, since if the backsheet film alone were placed on a flat surface, even if the backsheet film 55 may also not be flat when comprised in for example an absorbent article not flat according to an alternative embodiment of the present invention. The backsheet film 55 also comprises openings 53 that form capillaries 54. As best illustrated in Figure 2, which shows a cross-sectional view of an individual capillary 54 of the backsheet polymer film 55, the capillaries 54 have side walls 56 that extend away from the surface that gives the user of the polymeric film of the backsheet 55 toward the absorbent core 40, 42, 44. The capillaries 54 have a first opening 57 in the plane of the surface that the garment of the polymeric film of the backsheet 55, and a second aperture 58 of the end of the capillaries 54 which is itself separate from the user-facing surface of the backsheet polymer film 55. Each capillary 54 defines a conduit 70 constituted by the first opening 57, the second opening 58, and the side walls 56. Each capillary 54 also has a central line A defined as the geometric axis of The conduit 70. In the embodiment of Figure 2, where the conduit 70 has a cylindrical shape, the central line A simply corresponds to the straight line constituting the axis of the cylinder and which is perpendicular to the plane P of the rear sheet film 55. In the alternative embodiments of the present invention, where the conduit 70 defined by the capillaries 54 may have different shapes, such as for example those illustrated in Figures 3 to 7, the center line A is not necessarily a straight line, but can be at least a partially curved line that corresponds to the axis of the conduit, identified as it is known from the solid geometry. In the highly preferred embodiments of the present invention as those illustrated in the accompanying drawings where the sectional views of Figures 2 to 7 are taken from a plane of symmetry perpendicular to the plane P of the backsheet film, the identification of the central line A of the duct 70 can be more simply made on these same views in section, since said central line A is totally located on this plane of symmetry. For example, in the region where the duct 70 is joined to the plane P of the backsheet film 55 in Figures 3 to 7 the identification of the center line A as the axis of the duct 70 should be taken into consideration the fact that the duct 70 typically does not have a regular shape in this region as compared to the remaining portion of the capillary 54 where the duct 70 is fully defined as a cylinder or a truncated cone and wherein the center line A is defined in front. A good approach to identify the center line A in this junction region is to connect the points to the center of some sections of the conduit 70 which are parallel to the plane P, and are taken at different distances from the plane P (whose surfaces of the course correspond to segments parallel to the plane P in the sectional views of the drawings). This practical method can be used to draw or draw the center lines in the conduits 70 illustrated in Figures 3 to 7. This is also consistent with the identification of the point of intersection between the center line A and the surface of the first opening 57 in the plane P of the backsheet film 55, as will be explained hereinafter. The first opening 57 of the capillary 54 on the surface of the rear sheet polymer film garment 55 has a smaller dimension Dm? N and a larger dimension Dmax respectively defined as the minimum and maximum opening measurements within the area of the first opening 57 in the plane of the surface that gives the garment of the backsheet polymer film 55 (plane P), i.e., being measured when the surface that gives the garment of the backsheet polymer film 55 is placed on a flat surface. The smaller and larger dimensions Dm? N and Dmax can be evaluated by means known in the art, such as for example by image analysis techniques. The average dimension Dav can also be evaluated for the first opening 57, as corresponding to the hydraulic diameter of a duct having the same cross section as the first opening 57 in the plane of the surface that gives the garment the rear sheet polymer film 55, wherein the total perimeter of the first opening 57 is wetted by the fluid. Of course the concept of "hydraulic diameter" is used here as a definition only, since the conduit 70 of the capillaries 54 is not intended for the transport of liquids, and the term "fluid" is therefore used in the meaning wider comprising gaseous fluids, especially air and / or water vapor. As is well known from hydraulic, the hydraulic diameter of a duct having a cross-sectional area and a wet perimeter corresponds to four times the ratio between the cross-sectional area and the wetted perimeter, which instead corresponds to this context to the total perimeter of the cross-sectional area of the first opening 57. In the embodiment illustrated in Figure 2, where the duct 70 has the shape of a cylinder having a certain diameter, the first opening 57 in the surface that gives The garment of the backsheet polymer film 55 typically has a circular shape with a diameter slightly larger than the diameter of the cylindrical conduit 70, attributable to the curvature imparted to the film 55 around the first aperture by, for example, the method and apparatus of manufacture used for the formation of the back sheet polymer film 55.

In this case this is the largest diameter corresponding to the largest dimension Dmax of the first opening 57. Of course in the case of Figure 2, where the first opening 57 has a circular shape, the values of Dmm and Dmax correspond. Each capillary 54 also has a length L measured along the center line A between the first opening 57 and the second opening 58. The length L is intended to be measured along the center line A between two points of intersection Pi and P2 defined as follows. The first point Pi corresponds to the intersection of the center line A with the surface Si of the first opening 57. Said surface Si is flat, as can be seen in the modalities illustrated in the drawings, and resides in the plane of the surface that gives the garment of the backsheet polymer film 55 (plane P). From a practical point of view, in the embodiments of the present invention such as those illustrated in Figures 2 to 7, the first point Pi corresponds to the center of the first surface Si, as already explained with reference to the identification of the central line A of the duct 70 of the capillaries 54 having different shapes. The second point P2 corresponds to the intersection between the center line A of the duct 70 and a flat surface S2 that is perpendicular to the center line and passes through the point or points of the perimeter of the second opening 58 which is / is closer to the first respective opening 57 of the capillary 54, where the distance along the internal surface of the side wall 56 of the capillary 54 is evaluated. These measurements can also be obtained with methods known in the art, for example by means of image analysis performed on photomicrographs of the back sheet polymer film 55 taken with an electron scanning microscope. In the embodiment of Figure 2, where the capillary 54 has a regular cylindrical shape, and the second opening 58 also has a circular regular perimeter, the flat surface S2 perpendicular to the center line A which identifies the intersection point P2 corresponds to a circular flat surface passing through the total perimeter of the second opening 58. It is generally preferred that the second opening 58 be as smooth as possible so as not to create a liquid transporting involvement between the extension elements at the end of the second opening 58 of the capillary 54 with the absorbent core 44 in the absorbent article (in contrast it may be desirable to use said film as an upper sheet of film with openings where said loose elements provide the function of suction feet to increase the transport of liquid). However, in other cases, and depending on the method used for the formation of the backsheet polymer film 55, the perimeter and the shape of the second opening 58 may not be regular. For example, the edge of the second opening 58 may be rough or uneven, comprising loose elements extending from the edge of the opening, as illustrated in Figure 4. In this embodiment, the surface Si is of course located in the plane of the pledge surface of the backsheet polymer film 55, such as the corresponding surface Si of Figure 2, while the surface S2, defined as explained above with reference to the identification of the second point P2, it is indicated as a section in Figure 4 with a dotted line. Figures 3 to 7 show by way of example the center lines A and the corresponding features Si, S2, Pi, P2, in capillaries 54 having different and less regular shapes, as compared to the regular shape of a straight cylinder. perpendicular to the plane of the polymer film 55. Usually the center line A passes through the first point Pi which corresponds to the center of the surface Si, identified by the regular and irregular shapes of the surface Si as it is known from the geometry flat In the section view of Figure 6, the dimensions Dm? n, Dav, and Dma of the first opening 57 coincide, as is the case with the capillary of Figure 2, since it is considered that the first opening 57 has a circular shape in said figure. In contrast, in Figures 3 to 5 and 7 the surface Si typically has an elliptical shape, with the major axis shown in the sectional views. In these cases the dimension shown in these figures corresponds to the largest Dmax dimension as defined here. For each capillary 54 of the backsheet polymer film 55 comprised in the breathable absorbent article of the present invention, a relationship can be defined between the length L of the capillary 54, and the dimension D of the first respective aperture 57, where D can be correspond to Dmm, Dav, or Dmax. It has been found that by selecting this ratio or ratio it is possible to improve the operation of the three-dimensional resilient polymeric web in accordance with the present invention, preferably incorporated as the backsheet polymeric film 55 with capillaries 54 in the breathable backsheet of the absorbent article. disposable described thus far, in terms of increased breathability combined with better resistance to rewetting of the structure of the polymeric, resilient, three-dimensional web under pressure and stress, for example typically exerted by the user on a disposable absorbent article incorporating the polymeric web resilient, three-dimensional, in a backsheet structure, for example a sanitary napkin or pantiliner, during the time of use. The effect of elasticity and damping in response to compression forces exerted substantially perpendicularly to the surface of the polymeric film of the backsheet can also be improved in accordance with the present invention. This effect may also be desirable within the context of a non-breathable structure, for example, a non-respirable back sheet.

The ratio between the length L of the capillaries 54 and the smallest dimension Dm.n of the first opening 57 must be greater than 2. Preferably, the ratio between the length L and the average dimension Dav of the first opening 57 must be greater of 2, more preferably the ratio between the length L and the largest dimension Dmax of said first opening 57 must be greater than 2. Even more preferably, the ratio between the length L and either Dmin, Da, or Dma should be greater than 2.5 Without wishing to be bound by the theory it is believed that the capillaries in the preferred backsheet polymer film of the backsheet preferably breathable in the disposable absorbent article according to a preferred embodiment of the present invention, allow permeability to the air and water vapor, and at the same time can be easily bent attributable to the preferred ratio of L / D under the pressure exerted from the side that gives the suario on them by the user during the time of use. The bending causes the capillaries to close under pressure so that the transport of liquids through them, and towards the exterior of the article in the preferred embodiment described thus far, becomes almost impossible. Therefore, the three-dimensional resilient polymeric webs of the present invention are highly preferable in the context of breathable absorbent articles. This also affords the three-dimensional resilient polymeric web of the present invention corresponding to the backsheet polymer film 55 of the preferred embodiment, better elasticity and ability to provide a damping effect under pressures in use. As explained here above, in the case of a capillary having a first circular opening 57, the distinction between Dm, Da, and Dmax is not necessary or possible since the three relevant dimensions of D of the first opening 57 correspond one to others.

In the case of the capillaries 54 with a first opening 57 having a shape different from that of the circle the three relevant dimensions Dm¡n, Dav, and Dma? they really differ from each other. In order to better express the ease of bending under an external pressure of a capillary having a preferred UD ratio, one of the three relevant dimensions of the first opening may be more indicated, depending on the particular shape of the first opening, it is say, if it is regular or irregular, or that it has a perimeter that is internally concave in a total manner, such as for example circular, oval or elliptical, or alternatively partially concave and partially convex. In the latter case, the use of Dav or, more preferably of Dmax in the L / D ratio are preferred. In a particularly preferred embodiment of the present invention illustrated in Figures 3 to 8, the capillaries 54 of the backsheet polymer film They may also be inclined, ie arranged at an angle relative to the plane of the backsheet polymer film that is less than 90 degrees, or, alternatively, curved or bent toward the plane of the backsheet polymer film. Preferably a backsheet polymer film 55 can be made according to the aforementioned U.S. Patent No. 5,591, 510 or international publications WO 97/03818, WO 97/03795. Figures 3 to 7 show alternative modalities of said capillaries. Preferably, the capillaries are evenly distributed across the entire surface of the layer, and all are identical. However, layers having only certain regions of the surface provided with openings, for example only an area outside the region aligned with the central loading zone of the absorbent core, can be provided with capillaries according to the present invention. The methods for making such three-dimensional polymeric films with capillary openings are identical or similar to those found in the references of the upper sheet of film with openings, the references of the formed film with openings and the references of the micro / macroscopically expanded film cited above. Typically, a polymeric film such as a polyethylene film (LDPE, LLDPE, MDPE, HDPE or laminates thereof) is heated close to its melting point and exposed through a forming screen to a suction force which pulls the those areas exposed to the force in the forming openings which are configured in such a way that the film is formed in that form and, when the suction force is sufficiently high, the film breaks its end thereby forming an opening through the movie. Other film materials include polyesters, polyethers, polyvinyl alcohols and others. Continuous hydrophilic films that are substantially impermeable to liquid, but permeable to wet steam per se can also be used for the manufacture of three-dimensional polymeric films with capillary openings according to the present invention. Such films do not allow the flow of wet steam through open pores or openings in the material, but transfer substantial amounts of wet steam through the film by absorbing the water on one side of the film where the concentration of wet steam is higher, and it desorbs or evaporates on the opposite side of the film where the concentration of wet steam is lower. These films, referred to as monolithic films, are known in the art, such as for example the Hytrel (TM) film by DuPont, Corporation, USA. When a monolithic film is used to make a three-dimensional polymer film with capillary openings according to the present invention, it is capable of maintaining the breathability of the polymeric film with capillaries even in the area of the film where, under particularly stressed conditions of use, the capillaries are completely closed due to bending, under, for example, the high pressure exerted by the user. ^^ ai ^ Various shapes, shapes, sizes and configurations of the capillaries are possible and will be discussed with reference to Figs. 3 to 7 in the following. Figure 5 shows a cross-sectional view of a single inclined capillary 54 of a preferred backsheet polymer film made in accordance with U.S. Patent No. 5,591, 510 or international publications WO 97/03818, WO 97/03795, and which also has the required ratio between the length L and the dimension D of the first opening (57) according to the present invention, wherein the elements corresponding to those already described in Figure 2 are identified by the same numbers. The center line A forms along an at least part of its length an angle less than 90 degrees with the plane P of the film which is in the same plane as the surface that gives the garment of the film 55. This angle should preferably be in the range of between 85 and 20 degrees, more preferably between 65 degrees and 25 degrees, and most preferably between 55 and 30 degrees. An angle less than 90 degrees with the plane P can be formed by the center line A along its total length when, as illustrated in Figures 3 and 4, the center line A is substantially rectilinear or, as in the Figure 5, where the central line A is rectilinear along most of its length. This angle can be said to actually run at the inclined capillary angle. In alternative embodiments where the center line A is fully or partially curved, such as for example those illustrated in Figures 6 and 7, the angle of the center line A, as known from the geometry, corresponds to the angle of the tangent to the center line A at a given point, as measured in the sectional view illustrated in the figures themselves. Of course in these cases the angle can vary along the length of the center line A. It is within the scope of the present invention that the center line A forms an angle less than 90 degrees along at least a part of its length, but it is preferred that substantially the entire center line A, or at least most of it, forms a constant angle less than 90 degrees with the plane P, as illustrated in Figures 3, 4 and 5. , or alternatively, the angle changes continuously along the total length of the center line A, as illustrated for example in Figure 6 (curved capillary). It is of course possible to allow the capillaries to take the form of a funnel such that the second opening 58 is (substantially) smaller than the first opening 57 when considering the size of the opening in the plane perpendicular to the center line A. Blister embodiment is shown in Figure 4 and Figure 3. In Figure 3 it is also shown that the capillary wall 56 may not terminate in the second opening 58 so that the opening forms a surface perpendicular to the center line A but such that the wall in the capillary portion further away from the surface that gives the user of the film 55 extends over the opening to further assist the film in reducing the likelihood of liquid migration through the capillaries from the absorbent core on the side that gives the user of the film 55 to the side that gives the garment of the film (and cause leakage). In Figure 6 there is shown another embodiment of the capillaries useful for the present invention, which are curved along their length towards the surface that gives the user of the film 55. This has a similar effect as the extension of the wall 56 as shown in Figure 3. In Figure 7 another preferred embodiment of the capillary according to the present invention is shown which has a first portion 257 and a second portion 258. The first portion 257 of the capillary is different in that direction. the second portion 258 of the capillary 54. This difference can also be in the form, size, and figure of the portions of the capillary in order to obtain the desired level of breathability while preventing the passage of liquid through the film in a direction from the side that gives the user towards the side that gives the garment . The preferred shape and size of the capillaries 54 having the required L / D ratio in a three-dimensional resilient polymeric web, which preferably constitutes the three-dimensional polymeric film 55 comprised in a preferably breathable backsheet structure of an absorbent article, in accordance with A preferred embodiment of the present invention described thus far can be determined by the person skilled in the art taking into account the end use of the polymeric web, for example in order to allow good water vapor permeability, also preferably air permeability, to the structure of the backsheet preferably comprising said frame. Preferably, the capillaries 54 have a first opening 57 with a dimension D generically comprised between 0.2 mm and 5 mm, wherein D comprises the smallest dimension Dmm, the average dimension Dav, and the largest dimension Dmax, as defined herein. When the first opening 57 has a circular shape, the dimensions Dmm, Dav, and Dmax, coincide, and correspond to said dimension D. These are preferably between 0.4 mm and 2 mm, more preferably between 0.7 mm and 1.5 mm. If, as is preferred, the first opening 57 has a substantially elliptical shape, with a Dmm and a Dmsx corresponding to the two axes of the ellipse, both Dmm and Dma? they are also more preferably comprised between 0.7 mm and 1.5 mm. In an example according to the present invention, where the three-dimensional resilient polymeric web is preferably comprised in a backsheet structure such as the three-dimensional backsheet polymeric film 55 of Figure 1, the capillaries 54 have a funnel shape that corresponds substantially to that illustrated in Figure 4, with the center line A forming an angle of approximately 35 degrees with the plane P of the film, where Dmm is 0.9 mm, Dmax is 1.1 mm, and L is 1.9 mm . In the preferred embodiments of the present invention comprising the three-dimensional resilient polymeric web as the backsheet of polymeric film 55 with inclined capillaries it is believed that said capillaries allow for air and water vapor permeability which is not obstructed by them being inclined at an angle or by the way as indicated above. At the same time the inclination and configuration according to the present invention further helps the capillaries having the preferred ratio between the length L and the dimension D of the first opening 57 to close under pressure exerted from the side that gives the user on them so that the transport of liquid through the capillaries to the outside of the article becomes almost impossible. Therefore, these three-dimensional film layers formed are highly preferable in the context of the disposable absorbent articles. An advantage related to the three-dimensional resilient polymeric web, which has inclined capillaries and which is comprised in a backsheet of a disposable absorbent article, is the fact that said three-dimensional film does not allow direct passage through its thickness, ie, as length of a direction perpendicular to the total surface of the film. Therefore it prevents parts of an additional layer or material adjacent or applied to a surface of the three-dimensional polymeric film with inclined capillaries from getting direct access to the opposite surface through the thickness of the film, ie through of the inclined capillaries. This is particularly useful in the context of a breathable back sheet. The inclined capillaries in fact prevent that a bridge can be created between the two surfaces of the three-dimensional polymer film, for example allowing the fibers of an adjacent fibrous layer to penetrate the capillary openings and achieve contact with an additional layer adjacent to the opposite surface, thus creating a preferred passage for the -J J fluid. Furthermore, when adhesive is used to join the three-dimensional polymer film to an adjacent layer, the inclined geometry of the capillaries does not allow part of the adhesive to penetrate through the capillaries and emerge on the opposite surface, possibly in contact with another layer and again create a bridge through the three-dimensional movie. According to a preferred alternative embodiment of the present invention, a preferably breathable backsheet 50 which is a double or multi-layer composite material may also be useful in the absorbent article. The respirable backsheets suitable for use herein may therefore comprise a layer such as the backsheet polymer film 55 as described above and a second layer with said first layer being an air permeable layer. The preferred breathable composite backsheets are those that have a high vapor exchange, most preferably both a high vapor exchange and a high air exchange. As illustrated in Figure 8, the first layer is a backsheet polymer film similar to that already described with reference to Figure 1, but with the capillaries 54 which are inclined. It has to be distinguished that the backsheet polymer film 55 is represented in FIG. 8 only schematically, in order to show the general arrangement of the layers comprised in a breathable composite backsheet, since the drawings do not really show the L / D ratio required according to the present invention. Of course, in accordance with the present invention, the embodiment of Figure 8 has to be actually attempted as well as comprising the required L / D ratio for the capillaries 54 of the backsheet polymeric film 55. The backsheet polymeric film 55 it is positioned between the garment-facing surface of the absorbent core 40, 42, 44 and the user-facing surface of the second layer which is indicated as layer 52 in Figure 8. This is oriented in a manner that retards or it prevents the passage of liquid from the absorbent core 40, 42, 44 to the outside while allowing the free flow of air therethrough. The second layer 52 needs to provide at least the water vapor permeability to maintain the breathability of the article. It is not required but it is desirable that it also maintain air permeability in order to further improve the comfort benefit of the breathability of the article. In this context suitable water vapor and air permeable layers include micro and macro perforated two dimensional films, which may also be micro or macroscopically expanded films, films formed with apertures and monolithic films, as well as nonwoven or woven materials. Suitable two-dimensional flat layers of the backsheet can be made of any material known in the art, but are preferably made from commonly available polymeric materials. Suitable materials are for example Goretex (TM) or Sympatex (TM) type materials well known in the art for their application in so-called breathable garments. Other suitable materials include XMP-1001 from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota, USA and Exxaire XBF-101W, supplied by Exxon Chemical Company. As used herein, the term "two-dimensional flat layer" refers to the layers having a depth of less than 1 mm, preferably less than 0.5 mm, wherein the openings do not protrude from the plane of the layer. Materials with openings for use as a backsheet in the present invention can be produced using any of the methods known in the art such as described in European Patent EP 293482 and references thereto. In addition, the dimensions of the openings produced by this method can be increased by applying a force through the plane of the backsheet layer (i.e., stretching the layer).

The films formed with suitable apertures include films having discrete apertures, which extend beyond the horizontal plane of the surface which gives the garment of the layer to the core thus forming protuberances. The protuberances have a hole located at their terminal end. Preferably said protuberances are of a funnel shape, similar to that described in U.S. Patent No. 3,929,135. The openings located within the plane and the holes located at the terminal end of the protrusion itself can be circular or noncircular as long as the dimension or cross-sectional area of the hole at the termination of the protrusion is smaller than the dimension or section area cross section of the opening located inside the surface that gives the garment the layer.

Preferably said preformed films with openings have a directional transport of liquid and are positioned so that they maintain the prevention of liquid leakage (leakage) through the backsheet. Macroscopically expanded films suitable for use herein include the films as described, for example, in U.S. Patent No. 4,637,819 and in the US Pat.

United No. 4,591, 523. Suitable monolithic films include Hytrel (TM), available from DuPont Corporation, USA, and other such materials as described in Index 93 Congress, Session 7A "Adding Value to Nonwovens", JC Cardinal and Y. Trouilhet, DuPont Nemours International SA Switzerland. Suitable nonwovens and / or fabrics are any of those well known in the art. Non-woven materials such as spin-bonded, meltblown or carded materials which are placed with thermally bonded air, placed dry or even wet laid with or without binder can be used. Particularly preferred nonwoven materials are multilayer nonwoven materials such as a composite material of thin fibers blown in the molten state with thicker spunbonded fibers with the blown fibers in the molten state forming the surface that gives the wearer the layer non-woven Construction of absorbent article A further aspect of the present invention relates to the joining of the elements, for example the upper sheet, the back sheet and the absorbent core, to provide the article comprising the three-dimensional resilient polymeric web of the present invention, for example the disposable absorbent article described so far, when the three-dimensional resilient polymeric web of the present invention is actually comprised in an article, instead of being used as such. According to the present invention at least two, preferably all the elements of the article are joined. Each of the elements comprising at least one layer has a surface that gives the body and a surface that gives the garment. Typically, the adjacent garment facing surfaces form a common interface with the surface that gives the wearer an adjacent element or layer. The elements or layers are joined together through their common interface. In this manner, the top sheet is attached to the absorbent core, and the core is attached to the backsheet. In addition, each of the elements of the upper sheet, back sheet and core may comprise more than one layer and these layers may also be joined in a similar manner. In addition, the topsheet can be directly or indirectly attached to the backsheet at the periphery of the absorbent article. The elements and the layers thereof can be joined by any of the means known in the art to fix two layers of adjacent material, so that the layers are directly fixed to each other or directly fixed to each other by means of joining means . Suitable bonding means include adhesive, fusion bonding, ultrasonic bonding, sewing, heat (for example thermo joining by welding fibers at intersections or melting a polymer to fix the fibers or films together), pleating, embossing, and / or snap connections, mechanical dynamic joints or combinations from the same. According to one embodiment of the present invention, the preferred joining means is adhesive. Suitable adhesives include adhesives not sensitive to pressure and cold. The adhesive can be applied by any means known in the art such as application in the form of lines, spiral application, slot coating, sprinkling, spiral sprinkling, curtain coating, control coating and printing, provided the adhesive does not substantially affect the breathability, in the embodiment of the present invention of a breathable absorbent article, and other functions of the elements of the article. One means to achieve this is to use particular methods of adhesive application such as open adhesive application techniques, whereby the areas of the common interface are free of adhesive, while retaining the required level of attachment / bonding of the two layers or adjacent elements. In particular it is preferred to be spiral sprayed. In a preferred embodiment of the present invention wherein the absorbent article finds utility as a sanitary napkin or a pantiprotector, the absorbent article is also provided with a panty fastening means which provides the means to secure the article to an undergarment. For example, the panty fastener means may comprise a mechanical fastener such as hook and loop fasteners as sold under the tradename VELCRO, snaps or fasteners. Alternatively, the article is fastened to the undergarment by means of the panty fastener adhesive on the back sheet. The panty fastener of the panty provides a means for securing the article to the panty and preferably «.iot-i ... .. .. .. - « »» »Jb-f. ^. »Aafc¿ a means to secure the item when it gets dirty, to fold and wrap the package for convenient disposal. Typically, at least a portion of the garment surface of the backsheet is coated with the adhesive to form the panty fastener adhesive. Any adhesive or glue used in the art for such purposes can be used for the panty fastener adhesive herein.

Pressure sensitive adhesives are very preferred. Suitable adhesives include Century A-305-IV manufactured by Century Adhesives Corporation of Columbus, Ohio, and Instant LOK 34-2823 manufactured by National Starch and Chemical Company of Bridgewater, New Jersey, 3 Sigma 3153 manufactured by 3 Sigma and Fuller H- 2238ZP manufactured by HB Fuller Co. In order to reduce the breathability effect of the backsheet (and therefore of the article as a whole) in the preferred breathable absorbent articles, the adhesive is preferably applied so that at least 60%, preferably at least 80%, most preferably at least 90% of the surface of the backsheet is free of adhesive. The required adhesiveness can still be achieved even when reduced surface protection is used using a particular distribution such as thinner strips, discontinuous adhesive strips, intermittent dots, random patterns or spirals. The panty fastener adhesive is typically protected with a removable release paper or film to prevent the adhesive from drying or adhering to a different surface of the panty before use. Any commercially available release paper or film can be used. Suitable examples include BL 30MG-A SILOX El / O and BL 30 MG-A SILOX 4 P / O available from Akrosil Corporation. According to the present invention, the resilient, three-dimensional polymeric frames can be used beneficially within the context of sanitary napkins, pantiliners, incontinence articles, sweat pads and diapers, as well as protective articles such as gowns, facial masks and bandages. However, sanitary napkins are particularly susceptible to the present invention. The disposable article can thus also have all those characteristics and parts that are typical for products in the context of their intended use.

Claims (10)

1. A perforated, resilient, three-dimensional plastic web, said web consisting of a polymeric film impervious to liquid (55) having a first surface, a second surface, and openings (53), said openings (53) forming capillaries (54), having the capillaries (54) side walls (56) extending away from the second surface of the film (55), said capillaries (54) having a first opening (57) in said first surface of the film (55), said first opening (57) having a smaller dimension Dmin, an average dimension Dav, and a larger dimension Dmax, and a second opening (58) at the end of the capillaries (54) separated from the second surface of the film (55), each of the capillaries (54) defining a conduit (79), said conduit constituted by said first opening (57), said second opening (58), and the side walls (56), each of the capillaries (54) having a central line A defined as the geometric axis of said conduit (70), and a length L measured along the center line A between two points Pi and P2 respectively corresponding to the first opening (57) and to the second opening (58), said frame being characterized in that the ratio between the length L and said smaller dimension Dmin of said capillaries (54) is greater than 2. 2. A perforated, resilient, three-dimensional plastic frame, according to claim 1, characterized in that the ratio between the length L and said average dimension Dmax is greater than

2.

3. A perforated, resilient, three-dimensional plastic web, according to claim 1, characterized in that the ratio between the length L and the largest dimension Dmax is greater than 2. & A - ^

4. A perforated, resilient, three-dimensional plastic web according to any of claims 1 to 3, characterized in that the ratio is greater than 2.5

5. A perforated, resilient, three-dimensional plastic web, according to any of the preceding claims, characterized in that the center line A forms along an at least part of the length L an angle smaller than 90 ° measured from the plane of the film.

6. A perforated, resilient, three-dimensional plastic web according to any of the preceding claims, characterized in that at least some of the capillaries form cylinders having section areas that are constant in a direction extending away from the second surface when it is compared to areas perpendicular to the center line A.

7. A perforated, resilient, three-dimensional plastic web according to any of the preceding claims, characterized in that the capillaries (55) have said smaller dimension Dm.ny and said larger dimension Dmax comprised between 0.2 mm and 5 mm, preferably between 0.4 mm and 2 mm, more preferably between 0.7 mm and 1.5 mm.

8. A perforated, resilient, three-dimensional plastic web, according to any preceding claim, characterized in that the perforated, resilient, three-dimensional plastic web is comprised in a breathable backsheet of a breathable disposable absorbent article.

9. A disposable absorbent article having a surface that gives the garment, which is oriented to give in the direction of a garment (21) during the use of the article, and a surface that gives the user, which is oriented to give at the address of the user (20) during the use of the article, said article comprising at least a liquid permeable top sheet (30); a back sheet (50); an absorbent core (40, 42, 44) comprised between the top sheet (30) and the back sheet (50); said backsheet (50) comprising at least one resilient, three-dimensional web, said web consisting of a liquid-impermeable backsheet film (55) having a surface that gives the garment a surface that it gives to the user, and openings (53), said openings (53) forming capillaries (54), the capillaries (54) having side walls (56) extending away from the surface that gives the user of the backsheet film (55) toward said absorbent core (40, 42, 44), said capillaries (54) having a first opening (57) in the garment facing surface of the backsheet film (55), the first opening (57) having a smaller dimension Dm.n. an average dimension Dav, and a larger dimension Dmax, and a second opening (58) at the end of the capillaries (54) separated from said surface giving the user of the backsheet film (55), each of the capillaries (54) defining a duct (70) , said conduit constituted by the first opening (57), the second opening (58), and the side walls (56), each of the capillaries (54) having a central line A defined as the geometric axis of said conduit (70), and a length L measured at along the center line A between two points Pi and P2 corresponding correspondingly to the first opening (57) and to the second opening (58), the article being characterized in that the ratio between the length L and the smallest dimension Dmm of said capillaries (54) is greater than 2. m t .- -,

10. A disposable absorbent article according to claim 9, characterized in that the disposable absorbent article is breathable, wherein said back sheet is also breathable. -jM --- M-l-É-Í - t - iiá-á- & -fc «.t» ..__. . . . , - a.a -.t r, bt¡u? * Mmm¡s